Simple and Facilitated Diffusion exam Flashcards

Direct diffusion of small uncharged molecules through the cell membrane without the help of membrane proteins.

Passive transport of charged molecules across the membrane with the help of transport proteins.

Movement of molecules across the cell membrane without the need for energy input.

Simple diffusion does not require transport proteins, while facilitated diffusion does.

A difference in the concentration of a substance across a space.

Small uncharged molecules.

Proteins that assist in the movement of molecules across the cell membrane in facilitated diffusion.

Transport proteins that form membrane-spanning tunnels to allow molecules to pass through.

Transport proteins that undergo conformational changes to move molecules across the membrane.

They specifically transport water molecules across the cell membrane, facilitating osmosis.

The diffusion of water across a semipermeable membrane.

Transport proteins such as porins and carriers.

Neither simple diffusion nor facilitated diffusion requires energy input.

Charged molecules (ions).

A structure formed by porins to allow molecules to pass through the membrane.

They allow ions to move through the membrane-spanning tunnels created by porins.

A change in the shape of a carrier protein that allows it to transport molecules across the membrane.

To move from areas of high concentration to areas of low concentration.

The maintenance of stable internal conditions in a cell.

To assist charged molecules in crossing the cell membrane.

Specialized porins that facilitate the transport of water molecules.

It requires no energy input.

Channels that allow ions to pass through the cell membrane in facilitated diffusion.

They undergo conformational changes to transport molecules.

To maintain cellular homeostasis and nutrient absorption.

A type of passive transport.